With so many people excited (and enraged) about iPhone 3GS, it's no wonder we glossed over Snow Leopard's cool UI update, which gives you Exposé control from inside the Dock. Now's your chance to see the video demo:

As John mentioned yesterday, it's an update that resembles Windows 7's amazing Taskbar, in that you can get at more windows and files from the Dock itself, currently considered more of an app launcher than an app manager. Here are the new key attributes for Exposé, and how it works within the Dock:

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• Exposé itself has a new look: Windows are arranged in a grid rather than in whatever open space is available, and the title of each window appears underneath. (You can see this in the video below, if you pay attention.)

• Stacks, those folder contents that pop up from the Dock, also got tweaked. Most notably, you can scroll to see all the stuff in a stack without clicking the "More" arrow, and folders that appear in stacks can be opened and browsed, too.

• If you click and hold an app icon in the Dock, all the windows open in that app will reveal themselves in the Exposé grid, lined up neatly. Using some key command or cursor gesture (which I don't know), you can even zoom in to one of the open windows, and check it out without leaving Exposé.

• If you grab a file, you can drag it to the dock and hold it over an app icon. This springs open App, and arranges the open windows of that app in Exposé, so you can easily drop the file where it needs to go. (I currently do this by holding the file with my mouse while doing a combo-keystroke to bring the window back into view, so I can see how this will make life easier.)